It would be nice to have access to the interpolated generic vertex attributes in a fragment program. For example, in addition to fragment.color.primary and .secondary, get access to the interpolated values of the glVertexAttribArrays via fragment.attrib[n].
Aliasing could be the same in fragment programs as it is currently in vertex programs.
That would make it easier for more complex shaders to retrieve interpolated per-vertex input, especially if one needs more than one or two per-vertex vectors, and avoid the ‘abuse’ of color or texture coordinate arrays.
You can do that already. Just have your vertex program pass the value via a texture coordinate. You don’t actually have to use it for texturing.
You got a point there. I guess I should have read up on the VP parameter aliasing first 
Please disregard this post.